Scottie Mayfield is challenging Fleischmann in Tennessee's 3rd Congressional District Republican primary. Joe Hendrix, communications director for the elder Mayfield's campaign, emailed the Times Free Press about the confession and charge before the newspaper confirmed both with Nelson.

Michael Mayfield said he cut Threadgill's left rear tire stem during a stop on Mayfield's campaign bus tour Tuesday morning at the Roane County Courthouse, campaign and law enforcement officials said.

Threadgill and another Fleischmann aide said they attended the stop to monitor Mayfield's remarks.

The younger Mayfield admitted responsibility to his father at 8 a.m., Hendrix said.

"Within an hour and a half we were at the Kingston Police Department where Michael had told the police chief in a meeting that he had done [it]," Hendrix said.

Hendrix said the Michael Mayfield "gave a statement and was released." Nelson confirmed that account, adding that authorities will issue a citation and set a court date Friday.

Asked about the incident Wednesday, Scottie Mayfield denied having knowledge of the event and Hendrix said he didn't think anyone on the bus did the deed.

"This kind of activity has no place in campaigns and we are regretful that it happened," Scottie Mayfield said in a statement released today.

"Michael will be making his own apology to Mr. Threadgill and has made several attempts to reach him by phone today," Mayfield added in the statement. "Michael is prepared to make full restitution for the damage that was done to Mr. Threadgill's tire."